While most have already accepted that Lance Armstrong likely used performance-enhancing drugs at some point in his career, Hamilton and Coyle go further into the larger phenomenon, taking readers down a rabbit hole of malleable doctors, blind-eyed team directors, and athletes who push their bodies to the physical and moral limit. Was the USADA’s cry to “clean-up the sport” merely a disguised, personal witch hunt based on a specific vendetta against Armstrong? Perhaps, but the number of cyclists that have admitted to or been tested positive for doping has undoubtedly left not only scars, but gaping wounds on the sport of professional cycling. Guilty or not, this book fascinates and captures the sport in a definitive, albeit unflattering, way.

To view spectacular nature, one doesn't need to travel the world or buy a subscription to National Geographic Magazine -- you just need an Instagram account. Here are the 25 best adventure Instagram accounts you probably aren't following, yet.

The Briefing

Long gone are the days when the commuter bike was an old-school mountain bike with a potpourri of parts and a rear wheel that was only roughly true. A rise in people looking to build fitness, lower their carbon footprint or simply have fun while getting around has created a big market for commuter bikes. Here are some of our favorites for 2015.